62
E. Thermistor Check
To check thermistor resistance, follow the steps below.
1) Turn off the power supply.
2) Remove the front panel, then move the control switch to the "OFF" position.
3) Remove the control box cover.
4) Remove the thermistor.
5) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or
3 minutes.
6) Disconnect the white thermistor connector from CB WHITE K3 connector and check
the resistance between thermistor leads. Normal range is 4.7 to 6.2 kΩ. If outside
the normal range, replace the thermistor. See "V.B. Important Notes for Component
Replacement." If within the normal range, continue to the next step.
7) Replace the thermistor in its correct position. See "V.B. Important Notes for Component
Replacement."
8) Reconnect the white thermistor connector to CB WHITE K3 connector.
9) Replace the control box cover in its correct position, then turn on the power supply.
10) Move the control switch to the "ICE" position.
11) Once the harvest cycle starts, begin timing the harvest cycle.
12) The harvest timer should terminate and end the harvest cycle within 2 to 3 minutes. If
the harvest timer does not terminate and end the harvest cycle, the harvest timer is bad
and CB must be replaced.
Legend: CB–control board
F. Adjustment of Water Regulating Valve (water-cooled model)
WRV is factory set, and generally no adjustment is required. However, when necessary,
adjust WRV using the procedure below.
1) Prepare a thermometer to check the condenser drain temperature. Attach a pressure
gauge to the high-side line of the system.
2) Five minutes after a freeze cycle starts, conrm that the
thermometer reads 104°F to 115°F (40°C to 46°C). If it does
not, use a at blade screwdriver to rotate the adjustment
screw on WRV until the temperature is in the proper
range (rotate counterclockwise to raise the temperature or
clockwise to lower the temperature). See Fig. 3. Next, check
that the reference pressure is in the range indicated in the
Head Pressure table in the Performance Data section. If it is
not in the proper range, verify the refrigerant charge.
3) Check that the condenser drain temperature is stable.
Legend: WRV–water-regulating valve
Fig. 3
Adjustment Screw
CCW – Higher
CW – Lower
Top View